Sift together the flour, baking powder, salt and baking soda. Set aside.
In the large bowl of an electric mixer fitted with the paddle attachment, mix the butter with the lime zest on medium speed until smooth and creamy. Add the sugar in a steady stream and mix until thoroughly combined, about 2 minutes. Add the egg yolks, then add the lime juice and vanilla, mixing well for about 1 minute. Scrape down the sides of the bowl as needed.
Reduce the mixer speed to low and add the dry ingredients in two additions mixing until almost combined. Remove the bowl from the mixer, add the pistachios and finish mixing by hand.
Shape the dough into a mound, divide into quarters and roll each into a log 3.75cm (1 ½ in) in diameter - about 15cm (6 in) long. Wrap the logs with plastic*, twisting the ends tightly to secure. Refrigerate for 1 hour or until firm (this dough will keep in the refrigerator for up to 3 days or may be frozen for 1 month).
Preheat the oven to 350°F/180°C. Line two large baking sheets with baking paper.
Using a very sharp knife, slice the logs into 6mm (¼ in) thick slices, turning the roll every two or three cuts, and place 5cm (2in) apart on the prepared sheets.
Bake for 8-9 minutes, until the edges are lightly browned. Let stand for 2-3 minutes before loosening from the paper with a thin metal spatula. Transfer to a wire rack.
Store the cookies in an airtight container, layered between strips of wax paper, for up to 3 weeks.

* I always use baking paper and a ruler to shape cookie dough logs, like Martha does here – it works really well.

That's a great resolution, Patricia :) (very economical too, lol :) If I haven't cooked from a book I own, I might not have the tools required or it may just be awful.This would be great dipped in some white chocolate I bet!